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authorLinus Torvalds <torvalds@linux-foundation.org>2018-08-22 21:34:08 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2018-08-22 21:34:08 +0200
commitcd9b44f90763c3367e8dd0601849ffb028e8ba52 (patch)
treed1da0c2d49e3622fe51584a154ab383b3e783c1b /kernel/signal.c
parentMerge tag 'acpi-4.19-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/... (diff)
parentipc/util.c: update return value of ipc_getref from int to bool (diff)
downloadlinux-cd9b44f90763c3367e8dd0601849ffb028e8ba52.tar.xz
linux-cd9b44f90763c3367e8dd0601849ffb028e8ba52.zip
Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton: - the rest of MM - procfs updates - various misc things - more y2038 fixes - get_maintainer updates - lib/ updates - checkpatch updates - various epoll updates - autofs updates - hfsplus - some reiserfs work - fatfs updates - signal.c cleanups - ipc/ updates * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (166 commits) ipc/util.c: update return value of ipc_getref from int to bool ipc/util.c: further variable name cleanups ipc: simplify ipc initialization ipc: get rid of ids->tables_initialized hack lib/rhashtable: guarantee initial hashtable allocation lib/rhashtable: simplify bucket_table_alloc() ipc: drop ipc_lock() ipc/util.c: correct comment in ipc_obtain_object_check ipc: rename ipcctl_pre_down_nolock() ipc/util.c: use ipc_rcu_putref() for failues in ipc_addid() ipc: reorganize initialization of kern_ipc_perm.seq ipc: compute kern_ipc_perm.id under the ipc lock init/Kconfig: remove EXPERT from CHECKPOINT_RESTORE fs/sysv/inode.c: use ktime_get_real_seconds() for superblock stamp adfs: use timespec64 for time conversion kernel/sysctl.c: fix typos in comments drivers/rapidio/devices/rio_mport_cdev.c: remove redundant pointer md fork: don't copy inconsistent signal handler state to child signal: make get_signal() return bool signal: make sigkill_pending() return bool ...
Diffstat (limited to 'kernel/signal.c')
-rw-r--r--kernel/signal.c170
1 files changed, 83 insertions, 87 deletions
diff --git a/kernel/signal.c b/kernel/signal.c
index cfa9d10e731a..5843c541fda9 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -65,14 +65,14 @@ static void __user *sig_handler(struct task_struct *t, int sig)
return t->sighand->action[sig - 1].sa.sa_handler;
}
-static int sig_handler_ignored(void __user *handler, int sig)
+static inline bool sig_handler_ignored(void __user *handler, int sig)
{
/* Is it explicitly or implicitly ignored? */
return handler == SIG_IGN ||
- (handler == SIG_DFL && sig_kernel_ignore(sig));
+ (handler == SIG_DFL && sig_kernel_ignore(sig));
}
-static int sig_task_ignored(struct task_struct *t, int sig, bool force)
+static bool sig_task_ignored(struct task_struct *t, int sig, bool force)
{
void __user *handler;
@@ -80,12 +80,12 @@ static int sig_task_ignored(struct task_struct *t, int sig, bool force)
if (unlikely(t->signal->flags & SIGNAL_UNKILLABLE) &&
handler == SIG_DFL && !(force && sig_kernel_only(sig)))
- return 1;
+ return true;
return sig_handler_ignored(handler, sig);
}
-static int sig_ignored(struct task_struct *t, int sig, bool force)
+static bool sig_ignored(struct task_struct *t, int sig, bool force)
{
/*
* Blocked signals are never ignored, since the
@@ -93,7 +93,7 @@ static int sig_ignored(struct task_struct *t, int sig, bool force)
* unblocked.
*/
if (sigismember(&t->blocked, sig) || sigismember(&t->real_blocked, sig))
- return 0;
+ return false;
/*
* Tracers may want to know about even ignored signal unless it
@@ -101,7 +101,7 @@ static int sig_ignored(struct task_struct *t, int sig, bool force)
* by SIGNAL_UNKILLABLE task.
*/
if (t->ptrace && sig != SIGKILL)
- return 0;
+ return false;
return sig_task_ignored(t, sig, force);
}
@@ -110,7 +110,7 @@ static int sig_ignored(struct task_struct *t, int sig, bool force)
* Re-calculate pending state from the set of locally pending
* signals, globally pending signals, and blocked signals.
*/
-static inline int has_pending_signals(sigset_t *signal, sigset_t *blocked)
+static inline bool has_pending_signals(sigset_t *signal, sigset_t *blocked)
{
unsigned long ready;
long i;
@@ -138,20 +138,21 @@ static inline int has_pending_signals(sigset_t *signal, sigset_t *blocked)
#define PENDING(p,b) has_pending_signals(&(p)->signal, (b))
-static int recalc_sigpending_tsk(struct task_struct *t)
+static bool recalc_sigpending_tsk(struct task_struct *t)
{
if ((t->jobctl & JOBCTL_PENDING_MASK) ||
PENDING(&t->pending, &t->blocked) ||
PENDING(&t->signal->shared_pending, &t->blocked)) {
set_tsk_thread_flag(t, TIF_SIGPENDING);
- return 1;
+ return true;
}
+
/*
* We must never clear the flag in another thread, or in current
* when it's possible the current syscall is returning -ERESTART*.
* So we don't clear it here, and only callers who know they should do.
*/
- return 0;
+ return false;
}
/*
@@ -529,13 +530,15 @@ flush_signal_handlers(struct task_struct *t, int force_default)
}
}
-int unhandled_signal(struct task_struct *tsk, int sig)
+bool unhandled_signal(struct task_struct *tsk, int sig)
{
void __user *handler = tsk->sighand->action[sig-1].sa.sa_handler;
if (is_global_init(tsk))
- return 1;
+ return true;
+
if (handler != SIG_IGN && handler != SIG_DFL)
- return 0;
+ return false;
+
/* if ptraced, let the tracer determine */
return !tsk->ptrace;
}
@@ -709,14 +712,14 @@ void signal_wake_up_state(struct task_struct *t, unsigned int state)
*
* All callers must be holding the siglock.
*/
-static int flush_sigqueue_mask(sigset_t *mask, struct sigpending *s)
+static void flush_sigqueue_mask(sigset_t *mask, struct sigpending *s)
{
struct sigqueue *q, *n;
sigset_t m;
sigandsets(&m, mask, &s->signal);
if (sigisemptyset(&m))
- return 0;
+ return;
sigandnsets(&s->signal, &s->signal, mask);
list_for_each_entry_safe(q, n, &s->list, list) {
@@ -725,7 +728,6 @@ static int flush_sigqueue_mask(sigset_t *mask, struct sigpending *s)
__sigqueue_free(q);
}
}
- return 1;
}
static inline int is_si_special(const struct siginfo *info)
@@ -742,21 +744,16 @@ static inline bool si_fromuser(const struct siginfo *info)
/*
* called with RCU read lock from check_kill_permission()
*/
-static int kill_ok_by_cred(struct task_struct *t)
+static bool kill_ok_by_cred(struct task_struct *t)
{
const struct cred *cred = current_cred();
const struct cred *tcred = __task_cred(t);
- if (uid_eq(cred->euid, tcred->suid) ||
- uid_eq(cred->euid, tcred->uid) ||
- uid_eq(cred->uid, tcred->suid) ||
- uid_eq(cred->uid, tcred->uid))
- return 1;
-
- if (ns_capable(tcred->user_ns, CAP_KILL))
- return 1;
-
- return 0;
+ return uid_eq(cred->euid, tcred->suid) ||
+ uid_eq(cred->euid, tcred->uid) ||
+ uid_eq(cred->uid, tcred->suid) ||
+ uid_eq(cred->uid, tcred->uid) ||
+ ns_capable(tcred->user_ns, CAP_KILL);
}
/*
@@ -907,16 +904,20 @@ static bool prepare_signal(int sig, struct task_struct *p, bool force)
* as soon as they're available, so putting the signal on the shared queue
* will be equivalent to sending it to one such thread.
*/
-static inline int wants_signal(int sig, struct task_struct *p)
+static inline bool wants_signal(int sig, struct task_struct *p)
{
if (sigismember(&p->blocked, sig))
- return 0;
+ return false;
+
if (p->flags & PF_EXITING)
- return 0;
+ return false;
+
if (sig == SIGKILL)
- return 1;
+ return true;
+
if (task_is_stopped_or_traced(p))
- return 0;
+ return false;
+
return task_curr(p) || !signal_pending(p);
}
@@ -996,7 +997,7 @@ static void complete_signal(int sig, struct task_struct *p, enum pid_type type)
return;
}
-static inline int legacy_queue(struct sigpending *signals, int sig)
+static inline bool legacy_queue(struct sigpending *signals, int sig)
{
return (sig < SIGRTMIN) && sigismember(&signals->signal, sig);
}
@@ -1380,14 +1381,15 @@ static int kill_proc_info(int sig, struct siginfo *info, pid_t pid)
return error;
}
-static int kill_as_cred_perm(const struct cred *cred,
- struct task_struct *target)
+static inline bool kill_as_cred_perm(const struct cred *cred,
+ struct task_struct *target)
{
const struct cred *pcred = __task_cred(target);
- if (!uid_eq(cred->euid, pcred->suid) && !uid_eq(cred->euid, pcred->uid) &&
- !uid_eq(cred->uid, pcred->suid) && !uid_eq(cred->uid, pcred->uid))
- return 0;
- return 1;
+
+ return uid_eq(cred->euid, pcred->suid) ||
+ uid_eq(cred->euid, pcred->uid) ||
+ uid_eq(cred->uid, pcred->suid) ||
+ uid_eq(cred->uid, pcred->uid);
}
/* like kill_pid_info(), but doesn't use uid/euid of "current" */
@@ -1500,8 +1502,7 @@ send_sig(int sig, struct task_struct *p, int priv)
return send_sig_info(sig, __si_special(priv), p);
}
-void
-force_sig(int sig, struct task_struct *p)
+void force_sig(int sig, struct task_struct *p)
{
force_sig_info(sig, SEND_SIG_PRIV, p);
}
@@ -1512,8 +1513,7 @@ force_sig(int sig, struct task_struct *p)
* the problem was already a SIGSEGV, we'll want to
* make sure we don't even try to deliver the signal..
*/
-int
-force_sigsegv(int sig, struct task_struct *p)
+void force_sigsegv(int sig, struct task_struct *p)
{
if (sig == SIGSEGV) {
unsigned long flags;
@@ -1522,7 +1522,6 @@ force_sigsegv(int sig, struct task_struct *p)
spin_unlock_irqrestore(&p->sighand->siglock, flags);
}
force_sig(SIGSEGV, p);
- return 0;
}
int force_sig_fault(int sig, int code, void __user *addr
@@ -1923,10 +1922,10 @@ static void do_notify_parent_cldstop(struct task_struct *tsk,
spin_unlock_irqrestore(&sighand->siglock, flags);
}
-static inline int may_ptrace_stop(void)
+static inline bool may_ptrace_stop(void)
{
if (!likely(current->ptrace))
- return 0;
+ return false;
/*
* Are we in the middle of do_coredump?
* If so and our tracer is also part of the coredump stopping
@@ -1942,19 +1941,19 @@ static inline int may_ptrace_stop(void)
*/
if (unlikely(current->mm->core_state) &&
unlikely(current->mm == current->parent->mm))
- return 0;
+ return false;
- return 1;
+ return true;
}
/*
* Return non-zero if there is a SIGKILL that should be waking us up.
* Called with the siglock held.
*/
-static int sigkill_pending(struct task_struct *tsk)
+static bool sigkill_pending(struct task_struct *tsk)
{
- return sigismember(&tsk->pending.signal, SIGKILL) ||
- sigismember(&tsk->signal->shared_pending.signal, SIGKILL);
+ return sigismember(&tsk->pending.signal, SIGKILL) ||
+ sigismember(&tsk->signal->shared_pending.signal, SIGKILL);
}
/*
@@ -2334,7 +2333,7 @@ static int ptrace_signal(int signr, siginfo_t *info)
return signr;
}
-int get_signal(struct ksignal *ksig)
+bool get_signal(struct ksignal *ksig)
{
struct sighand_struct *sighand = current->sighand;
struct signal_struct *signal = current->signal;
@@ -2344,7 +2343,7 @@ int get_signal(struct ksignal *ksig)
task_work_run();
if (unlikely(uprobe_deny_signal()))
- return 0;
+ return false;
/*
* Do this once, we can't return to user-mode if freezing() == T.
@@ -2801,7 +2800,7 @@ COMPAT_SYSCALL_DEFINE4(rt_sigprocmask, int, how, compat_sigset_t __user *, nset,
}
#endif
-static int do_sigpending(sigset_t *set)
+static void do_sigpending(sigset_t *set)
{
spin_lock_irq(&current->sighand->siglock);
sigorsets(set, &current->pending.signal,
@@ -2810,7 +2809,6 @@ static int do_sigpending(sigset_t *set)
/* Outside the lock because only this thread touches it. */
sigandsets(set, &current->blocked, set);
- return 0;
}
/**
@@ -2822,15 +2820,16 @@ static int do_sigpending(sigset_t *set)
SYSCALL_DEFINE2(rt_sigpending, sigset_t __user *, uset, size_t, sigsetsize)
{
sigset_t set;
- int err;
if (sigsetsize > sizeof(*uset))
return -EINVAL;
- err = do_sigpending(&set);
- if (!err && copy_to_user(uset, &set, sigsetsize))
- err = -EFAULT;
- return err;
+ do_sigpending(&set);
+
+ if (copy_to_user(uset, &set, sigsetsize))
+ return -EFAULT;
+
+ return 0;
}
#ifdef CONFIG_COMPAT
@@ -2838,15 +2837,13 @@ COMPAT_SYSCALL_DEFINE2(rt_sigpending, compat_sigset_t __user *, uset,
compat_size_t, sigsetsize)
{
sigset_t set;
- int err;
if (sigsetsize > sizeof(*uset))
return -EINVAL;
- err = do_sigpending(&set);
- if (!err)
- err = put_compat_sigset(uset, &set, sigsetsize);
- return err;
+ do_sigpending(&set);
+
+ return put_compat_sigset(uset, &set, sigsetsize);
}
#endif
@@ -3608,25 +3605,26 @@ int __compat_save_altstack(compat_stack_t __user *uss, unsigned long sp)
SYSCALL_DEFINE1(sigpending, old_sigset_t __user *, uset)
{
sigset_t set;
- int err;
if (sizeof(old_sigset_t) > sizeof(*uset))
return -EINVAL;
- err = do_sigpending(&set);
- if (!err && copy_to_user(uset, &set, sizeof(old_sigset_t)))
- err = -EFAULT;
- return err;
+ do_sigpending(&set);
+
+ if (copy_to_user(uset, &set, sizeof(old_sigset_t)))
+ return -EFAULT;
+
+ return 0;
}
#ifdef CONFIG_COMPAT
COMPAT_SYSCALL_DEFINE1(sigpending, compat_old_sigset_t __user *, set32)
{
sigset_t set;
- int err = do_sigpending(&set);
- if (!err)
- err = put_user(set.sig[0], set32);
- return err;
+
+ do_sigpending(&set);
+
+ return put_user(set.sig[0], set32);
}
#endif
@@ -3697,25 +3695,23 @@ SYSCALL_DEFINE4(rt_sigaction, int, sig,
size_t, sigsetsize)
{
struct k_sigaction new_sa, old_sa;
- int ret = -EINVAL;
+ int ret;
/* XXX: Don't preclude handling different sized sigset_t's. */
if (sigsetsize != sizeof(sigset_t))
- goto out;
+ return -EINVAL;
- if (act) {
- if (copy_from_user(&new_sa.sa, act, sizeof(new_sa.sa)))
- return -EFAULT;
- }
+ if (act && copy_from_user(&new_sa.sa, act, sizeof(new_sa.sa)))
+ return -EFAULT;
ret = do_sigaction(sig, act ? &new_sa : NULL, oact ? &old_sa : NULL);
+ if (ret)
+ return ret;
- if (!ret && oact) {
- if (copy_to_user(oact, &old_sa.sa, sizeof(old_sa.sa)))
- return -EFAULT;
- }
-out:
- return ret;
+ if (oact && copy_to_user(oact, &old_sa.sa, sizeof(old_sa.sa)))
+ return -EFAULT;
+
+ return 0;
}
#ifdef CONFIG_COMPAT
COMPAT_SYSCALL_DEFINE4(rt_sigaction, int, sig,